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bloblang-authoring

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This skill should be used when users need to create or debug Bloblang transformation scripts. Trigger when users ask about transforming data, mapping fields, parsing JSON/CSV/XML, converting timestamps, filtering arrays, or mention "bloblang", "blobl", "mapping processor", or describe any data transformation need like "convert this to that" or "transform my JSON".

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Marketplace

redpanda-connect-plugins

redpanda-data/connect

Plugin

redpanda-connect

development

Repository
Verified Org

redpanda-data/connect
8.6kstars

.claude-plugin/plugins/redpanda-connect/skills/bloblang-authoring/SKILL.md

Last Verified

January 18, 2026

Install Skill

Select agents to install to:

Scope:
npx add-skill https://github.com/redpanda-data/connect/blob/main/.claude-plugin/plugins/redpanda-connect/skills/bloblang-authoring/SKILL.md -a claude-code --skill bloblang-authoring

Installation paths:

Claude
.claude/skills/bloblang-authoring/
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Instructions

# Redpanda Connect Bloblang Script Generator

Create working, tested Bloblang transformation scripts from natural language descriptions.

## Objective

Generate a Bloblang (blobl) script that correctly transforms the user's input data according to their requirements.
The script MUST be tested before presenting it.

## Setup

This skill requires `rpk` `rpk connect`, `python3`, and `jq`.
See the [SETUP](SETUP.md) for installation instructions.

## Tools

### Script format-bloblang.sh

Generates category-organized Bloblang reference files in XML format.
**Run once at the start of each session** before searching for functions/methods.

```bash
# Usage:
./resources/scripts/format-bloblang.sh
```
- No arguments
- Generates category files organized by type (e.g., `functions-General.xml`, `methods-String_Manipulation.xml`)
- Outputs generated files to a versioned directory
- Outputs the directory path to stdout (capture in `BLOBLREF_DIR` variable for later use)
- Each XML file contains structured function/method definitions with parameters, descriptions, and examples

#### Functions

Generated function files have `functions-<Category>.xml` names and contain functions relevant to that category.

- `functions-Encoding.xml` - Schema registry headers
- `functions-Environment.xml` - Environment vars, files, timestamps, hostname
- `functions-Fake_Data_Generation.xml` - Fake data generation
- `functions-General.xml` - Bytes, counter, deleted, ksuid, nanoid, uuid, random, range, snowflake
- `functions-Message_Info.xml` - Batch index, content, error, metadata, span links, tracing IDs
- etc.

**The `function` XML tag format:**
- `name` attribute - function name
- `params` attribute - comma-separated list of parameters with types, format `<name>:<type>` or empty string if no parameters
- body - description of function purpose and usage
- `example` XML subtag
  - `summary` attribute (optional) - brief description of the example
  - body - code block demonstrating usage

Example functio

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